1. Field of the Invention
The invention relates to a process and a device for the manufacture of a primary unit pack of a wafer, particularly of a wafer that has been separated from an active substance film of one or more active substances for use as a dosage unit and administration form for medicaments.
2. Description of the Prior Art
Apart from the known dosage forms for medicaments, such as tablets, capsules, drops or similar administration forms, there is the administration form of the “wafer”. This is a small thin plate of an active substance film comprising a predetermined amount of active substance and with a thickness and dimensions adapted according to the amount of active substance to be delivered. A wafer is flexible, soft, of small weight and can be torn. Since there is a direct correlation between the contact surface of the wafer and the dosage amount of the active substance, the dimensions of the wafer must be identical to the greatest possible extent with the dimensions calculated, and must lie within the range of tolerance. Because the dosage is dependent on the surface area, the soft active substance material must not be stretched prior to cutting since otherwise the amount of active substance would be changed. For this reason, the manufacture of the wafer and the packaging of a single wafer or the packaging of several wafers in a primary pack unit is costly.
From DE 198 00 682 A1, a process is known for manufacturing a primary pack unit for film-like or wafer-like administration forms (wafers) for oral application, comprising one section of an upper packaging material web and one section of a lower packaging material web. When applied to square or rectangular wafers, the course of this process—which is in principle also applicable to unit packs of wafers—is different from that of the manufacture of wafers of another shape. For square or rectangular wafers, the first step is to convey an upper packaging material web and a lower packaging material web, without cold or hot forming, on top of one other via respective deflecting shafts, while the film-like or wafer-like administration form is simultaneously conveyed between the two webs of packaging material by means of rollers or gripper feed systems. In this process, it is also possible to feed an active substance film in the form of a web material—single-webbed or multi-webbed, parallel and spaced at a distance from one another—with the desired width of the dosage units. Subsequently, dosage units are singled out from the web-shaped active substance film by means of a cross-cutting apparatus which is positioned immediately in front of the deflecting shafts. In a further process step, the two webs of packaging material are sealed together with the help of a heated sealing tool in such a way that the single dosage units are sealed into compartments and are completely enclosed by sealed seams or sealed areas. In further process steps, perforations are punched between the compartments and primary pack units are partitioned off.
For wafers which are to have a shape other than square or rectangular, the process for the manufacture of the primary package unit according to DE 198 00 682 A1 is configured as follows: In a first process step, a laminate of the web-like active substance film and a carrier sheet is provided, out of which the dosage units are punched with a punching device in a further process step without punching through the carrier sheet. The partially punched laminate is subsequently rerouted over an edge or a deflecting shaft with the help of roller feed or gripper feed systems so that the dosage units thereby become detached from the carrier sheet. If necessary, an additional stripping device can be used for this purpose. Thereafter, an upper web of packaging material and a lower web of packaging material without cold or hot forming are conveyed on top of one another by means of respective deflecting shafts, whereby the dosage units becoming detached from the carrier sheet are simultaneously conveyed between the two webs of packaging material. Subsequently, the two webs of packaging material are sealed together with the help of a heated sealing tool in such a way that the single dosage units are sealed into compartments and are completely enclosed by sealed seams or sealed areas. In further process steps, perforations are punched between the compartments and primary packaging units are partitioned off. It goes without saying that this process can also be applied to the manufacture of square or rectangular wafers and the packaging thereof in primary unit packs.
Also known from the aforementioned DE 198 00 682 A1 are devices for carrying out the respective processes. One of these devices has a supply device for a laminate made up of an active substance film and a carrier sheet, a cutting or punching device for the active substance film for punching a wafer on the carrier sheet, a separating tool for detaching the active substance film from the carrier sheet, a pulling device for the carrier sheet, and thereby also for the active substance film with the wafer, a packaging material feeding and packaging material pulling device for two webs of packaging material which receive the respective wafer, a heated sealing tool for the packaging material, and a cutting tool for separating the sealed pouch.
The wafer material is elastic and may, as a consequence of the mechanical stress occurring when it is transported between the upper packaging material web and the lower packaging material web, change its shape and its dimensions. There is also a risk that the amount of active substance in the single wafer will change since the area of the wafer is decisive for dosing the active substance. With the above described processes it is not possible to ensure the required constancy of the active substance amount since the wafer material is in each case subjected to mechanical stress prior to being inserted between the packaging material webs.